Windows that support one or two tilt sash between jamb liners within a window frame are both popular and inexpensive, but they are less wind resistant than is desirable in regions subject to hurricanes. The sash must be free to tilt, which offers the users a highly desirable convenience, and the jamb liners must be resiliently mounted to seal against the sash and allow the sash to tilt; but this combination of requirements makes high wind resistance of the window difficult to achieve.
Several suggestions have been made to enhance the wind resistance of window sash supported between jamb liners, including the suggestions in U.S. Pat. Nos. 5,546,702 and 5,551,189. Pressure from the insurance industry for more wind resistant windows, along with more stringent building code requirements for wind resistance, have set standards that exceed the window strength attainable from such suggestions so that further improvement is needed.